1. Field of the Invention
This invention relates to electrically conductive plastic housings, principally for optics, optical sensors, electronic printed wiring boards and other systems and devices, the operation of which may be adversely affected by magnetic and/or radio frequency interference, for use in airborne detector systems and principally airborne missile guidance systems and the like.
2. Brief Description of the Prior Art
Guided airborne detector systems for dynamic airborne systems generally include, as a part of the airborne detector system, a detector guidance section for detecting target location and a control section for controlling airborne system trajectory in response to signals received from the detector guidance section in order to direct the airborne system to a selected target. Such detector and control systems must provide accurate and reliable outputs in order to insure that the desired trajectory is adhered to and that the ultimate target is reached. A problem with the detector and control electronics in such systems has been that magnetic and/or radio frequency interference emanating from the detector and/or the control section and/or other outside sources has been picked up by the airborne system electronics, thereby causing inaccurate readings to be provided, resulting in inaccurate trajectories with resultant failure to arrive at the desired target. For this reason, adequate shielding of the electrical components, cables and electrical interfaces between the detector, guidance and control sections of the airborne system has been critical to the accuracy and precision of the guidance which is required of the system.
In the prior art, this problem has been minimized by packaging and protecting electronic hardware and connections in the above described dynamic airborne systems from components fabricated from specially formed metallic housings, fastening hardware and interconnect components. The metallic forms were often expensive to produce, requiring tight tolerances at joint and cable interface areas. In view of the aerodynamic shape and size constraints of many airborne systems, especially those used for military purposes, the metallic forms are generally relatively expensive, require tight tolerances at joint and interface areas, require difficult swaging operations or adhesive based assembly and require extensive additional metallic fastening hardware for cable connections. Also, if thin metallic components were damaged or bent at joint areas prior to assembly, system protection could be severely compromised. Though systems of the type described above have been used for many years and represent the prior state of the art, it is apparent that such systems have significant drawbacks including high cost and intricate assembly methods.